Sorry should have been more specific. Go to Disk Utility, select your drive. Wipe it then go back and click Reinstall Mac OS X. Its worth nothing it will download the entire OS again so will take time.
Sorry should have been more specific. Go to disk Utility, select your drive. Wipe it then go back and click Reinstall Mac OS X. Its worth nothing it will download the entire OS again so will take time.
If that's what you want to do. However, clean installs are largely unnecessary.
Deleting everything just to put it all back is futile. You will have achieved nothing except emptied some caches and many be removed a tiny number of rarely used or unused files. It would be quicker and simpler simply to delete those instead.